Such hydraulic blocks are customary in modern hydraulic vehicle brake systems with braking force control. The braking force can take place there on a wheel-specific basis, on an axis-specific basis, for groups of vehicle wheels or jointly for all the vehicle wheels which can be braked. Examples of braking force control systems are an anti-lock brake control system (ABS), a traction control system (TCS) and/or an anti-skid or vehicle movement dynamics control system (ESP). Electro-hydraulic vehicle brake systems also have braking force control. Electro-hydraulic vehicle brake systems are extraneous force braking systems in which a hydraulic brake pressure is not built up by means of muscle force but rather as extraneous energy with a hydraulic pump. A braking force control operation for the purpose of what is referred to as “blending” can also take place in hybrid vehicles or electric vehicles. Electric vehicles have an internal combustion engine and at least one electric motor as drive motors, wherein the drive can optionally take place with the internal combustion engine, the electric motor or motors or jointly with the internal combustion engine and the electric motor or motors. In order to recover energy during the braking of the vehicle, the electric motor is operated as a generator and generates current which is stored in an accumulator and is made available for driving the vehicle with the electric motor. To be more precise, kinetic energy of the moving vehicle is converted into electrical energy which is referred to as “recuperation”. So that a vehicle driver notices as far as possible nothing, a braking force control operation reduces a braking force of the vehicle brake system in accordance with a braking torque of the electric motor in the generator mode. This is referred to as “blending”. It is possible to combine various braking force control operations.
Apart from an electronic component, such braking force controllers have a hydraulic part with usually one hydraulic pump for each brake circuit, solenoid valves, hydraulic reservoirs, nonreturn valves, pressure-limiting valves. The enumeration is neither conclusive nor complete. For example, in the case of a wheel-specific braking force control system, a braking force buildup valve and a braking force reduction valve are assigned to each wheel brake. Furthermore, a master brake cylinder is usually connected to the vehicle brake system by one isolating valve per brake circuit, in order to be able to disconnect said cylinder hydraulically from the vehicle brake system in order to lower a brake pressure. In order to be able to lower the wheel brake pressures quickly, a hydraulic reservoir is usually provided in each brake circuit and a wheel brake is connected hydraulically to said hydraulic reservoir in the case of a wheel-specific braking force control system by, in each case, one of the brake pressure reduction valves.
The hydraulic components of such vehicle brake systems are accommodated in a hydraulic block and connected to one another hydraulically by means of said block. The hydraulic block usually has an installation space for each hydraulic component, usually in the form of a (stepped) drilled hole into which the component is inserted. The hydraulic connection is usually carried out by means of drilled holes in the hydraulic block. The hydraulic block as such is usually a solid block-shaped component which is provided with the drilled holes. It permits a compact and stable design of the hydraulic part of the braking force control system of a hydraulic vehicle brake system, wherein by means of the installation of the hydraulic components, these are additionally also hydraulically connected to one another, which removes the need for a separate hydraulic connection of the individual hydraulic components.